Fluree is a ledger-backed semantic graph database with a cloud-native architecture.
AVL-Tree Inverted Index (Full Text)
https://flur.ee/
https://github.com/fluree/db
https://docs.flur.ee/
Fluree, PBC
US
2017
FlureeDB
Commercial, Open Source
Clojure
Clojure, JavaScript
All OS with Java VM
AGPL v3